<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title></title>
		<style>
			#hd{
				width: 300px;
				height: 300px;
				background: orange;
				/*占位置*/
				/*border: 3px solid red;*/
				/*不占位置*/
				outline: 3px solid red;
			}
		</style>
	</head>
	<body>
		<div id="hd">
			
		</div>
	</body>
</html>
